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Can i have some help rn?

Can i have some help rn?-example-1
User Guster
by
3.6k points

2 Answers

8 votes
  • Vertex at (-1,-4)
  • Passes through (1,0)

Find a

  • a(x-h)²+k=y
  • a(1+1)²-4=0
  • 4a-4=0
  • 4a=4
  • a=1

So

Vertex form

  • y=(x+1)²-4

#2

  • (h,k)=(4,-2)
  • passes through (6,6)

Find a

  • a(6-4)²-2=6
  • 4a=8
  • a=2

Vertex form

  • y=2(x-4)²-2
User Miron Balcerzak
by
4.1k points
1 vote

Answer:


\textsf{a)} \quad y=(x+1)^2-4


\textsf{b)} \quad y=2(x-4)^2-2

Explanation:

Vertex form of a parabola:
y=a(x-h)^2+k

(where (h, k) is the vertex and
a is some constant)

Part a

  • Vertex = (-1, -4)
  • Point on parabola = (1, 0)

Substitute the vertex into the formula:


\begin{aligned}\implies y &=a(x-(-1))^2-4\\y & =a(x+1)^2-4\end{aligned}

Substitute the point (1, 0) into the formula:


\begin{aligned}\implies a(1+1)^2-4&=0\\4a-4&=0\\4a &=4\\a &=1\end{aligned}

Therefore, the equation of the parabola in vertex form is:


y=(x+1)^2-4

Part b

  • Vertex = (4, -2)
  • Point on parabola = (6, 6)

Substitute the vertex into the formula:


\begin{aligned}\implies y &=a(x-4)^2+(-2)\\y & =a(x-4)^2-2\end{aligned}

Substitute the point (6, 6) into the formula:


\begin{aligned}\implies a(6-4)^2-2&=6\\4a-2 & =6\\4a &=8\\a &=2\end{aligned}

Therefore, the equation of the parabola in vertex form is:


y=2(x-4)^2-2

User Niklasbec
by
4.2k points